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A useful summary of the situation #Philae / #Rosetta is right to say, to avoid going to fish out all the previous messages.
The lander #Philae arrived successfully on the surface of the comet 67P yesterday. Has touched the ground three times, bouncing the first for nearly 1 Km in height, and the second for about 20 cm. We are far from the point of landing default (without the first bounce was centered with a difference of about 100 meters!) but still in a good area to carry out scientific studies.
However, #Philae is not firmly anchored to the surface as the two main hooks were not fired. The screws anchor the end of the tripod that supports it, however, are inserted (minimum 2/3) in soil comet, giving a minimum of stability.
The tools all function nominally, according to forecasts. The new landing site, however, shows less sunlight, and then will have to resort to a schedule to avoid complete discharge of the batteries before it come back again sunlight.
Now the priority is to find the exact location of the lander, and this will be done by the high-resolution images of #Rosetta which could come as early as today or tomorrow. “First comet drilling is a fact!” ESA posted on Twitter Friday night. Italian drill is working.http://www.theguardian.com/science/2014/nov/14/philae-comet-lander-drills-hammers-rosettaTools’ action will cause an opposite reaction in Rosetta’s Philae lander, perhaps nudging it into a more sunlit position.
Lander rotates into slightly sunnier position but apparently too late to charge batteries and keep systems running. Now is sleeping on the comet.
BERLIN, Germany (AP) —‚ The pioneering lander Philae completed its primary mission of exploring the comet’s surface and returned plenty of data before depleted batteries forced it to go silent, the European Space Agency (ESA) said yesterday.
“All of our instruments could be operated and now it’s time to see what we got,” ESA’s blog quoted lander manager Stephan Ulamec as saying.
Since landing Wednesday on comet 67P/Churyumov-Gerasimenko some 311 million miles (500 million kilometres) away, the lander has performed a series of scientific tests and sent reams of data, including photos, back to Earth. The science teams are now studying their data to see if they have sampled any of this material with Philae’s drill.
Data collected by Philae’s SESAME experiment suite support MUPUS results indicating the comet’s unexpected toughness. Early findings also show a low level of cometary activity at the probe’s landing site and a large amount of water ice under the lander, according to DLR.
“The strength of the ice founds under a layer of dust on the first landing site is surprisingly high,” said Klaus Seidensticker from the DLR Institute of Planetary Research, lead scientist on the SESAME instrument package, which was expected to study the comet’s composition and electrical, structural and mechanical characteristics.
While officials said Monday it was clear the drill worked, they could not say whether it gathered samples and deposited them in the lander’s instruments.
One of Philae’s sample analysis sensors — named COSAC — did collect data in “sniff” mode and detected organic molecules, presumably outgassing just above the comet’s surface.
SD2 principal investigator Amalia Finzi has reported that the drill was deployed as planned, extending 46.9 cm below the balcony of the lander and 56.0 cm from its reference point.
Although the ovens worked correctly, the scientists do not yet know how much – if any – material was actually delivered to the ovens by SD2, or whether the instruments sampled dust or gas that entered the chamber during the touchdown.
Because Philae was not anchored to the comet surface, it is also possible that, if the drill touched a particularly hard surface material, it moved the lander instead of drilling into the surface. Furthermore, the SD2 instrument lacks dedicated sensors to determine whether or not the surface has been reached, whether a sample was then collected in the sample tube, or if it was then discharged into the oven.
The lander also drilled into the comet’s surface in its hunt for organic molecules, but the latest results indicate that no soil was collected from the surface. So we only have data from what COSAC sniffed.

14 June 2015Lander Philae wakes up from hibernation
The first signals were received at ESA’s European Space Operations Centre in Darmstadt at 22:28 on 13 June.
Philae has an operating temperature of -35ºC and has 24 Watts available.
The scientists are waiting for more than 8000 data packets stored in Philae’s mass memory.